Speed Switch (Exc. B2000): 626

Connect voltmeter to Black/White and Green/Yellow wires of electrical connector. See Fig 2. Start engine and slowly increase engine speed. Record speed at which current flows through circuit (speed should be 1100-1300 RPM). Slowly decrease engine speed and note speed at which current stops flowing. Difference between readings should be 100-300 RPM. If not, replace engine speed unit.

Fig 1: Testing Mazda 626 Air Switching 3-Way Solenoid Valve

Courtesy of MAZDA MOTORS CORP.

Fig 2: Testing Mazda 626 Engine Speed Unit

Courtesy of MAZDA MOTORS CORP.